new: doc: prevent checking key for backup script

Signed-off-by: Valentin Lab <valentin.lab@kalysto.org>

README.org

@@ -743,7 +743,7 @@ dest="$BACKUP_SERVER"
 dest="${dest%/*}"
 dest="${dest%%:*}"
 echo "Contacting '$dest' host, to add key in authorized key:"
-ssh "root@${dest}" -- compose-add-rsync-key "\"$DOMAIN\"" "\"$(cat /root/.ssh/rsync_rsa.pub)\""
+ssh -o "StrictHostKeyChecking=no" "root@${dest}" -- compose-add-rsync-key "\"$DOMAIN\"" "\"$(cat /root/.ssh/rsync_rsa.pub)\""
 
 
 compose build mongo ## force the build of the new mongo image with regular dumps